Would a GOP Senate be king of the world?

If the Republicans win the Senate in November, the first thing they’ll say is: Finally, we can pass all of our bills and force President Barack Obama to deal with them.

The second thing they’ll say is: Oh, wait a second. This is the Senate.

That tension — between their desire to bring Obama to his knees and their ability to actually do it — is the political reality that will determine the Republicans’ legislative strategy if they win the Senate majority.

They’d love to set up clear contrasts between the parties and pave the way for 2016. But everything they do will be shaped by the limits of the Senate: What can they actually put on Obama’s desk without 60 GOP votes?

No one should underestimate the significance if the GOP captures the Senate in November — and while by no means a certainty, it is a very real possibility.

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Even with its limits, a Republican Senate would change the course of the Obama presidency for his final two years in office. Mitch McConnell, who would become majority leader if the Senate changes hands, is already promising to load up the appropriations bills with policy restrictions that could raise the risk of another government shutdown if Obama doesn’t sign them.

With both the Senate and the House in their hands, Republicans could put Obama on defense on everything from Obamacare to the administration’s greenhouse gas regulations, the Keystone XL pipeline, education policy and spending priorities.

They’d have a better chance of forcing the president to sign or veto changes to the health care law, a go-ahead for Keystone, House-passed jobs bills like the one that would make the research and development tax credit permanent — and a halt to greenhouse gas regulations.

And the oversight power alone would keep Obama administration officials busy with even more hearings. That’s something Senate Republicans can do with even the thinnest majority. Just by taking over the chairmanships of the committees, they could launch another round of hearings on the health care law, the IRS scandal, the mess at the Veterans Administration and the Environmental Protection Agency regulations. Some are even talking about reviving subjects like the release of Sgt. Bowe Bergdahl and the bungled Fast and Furious gun-walking operation.

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But that’s where the Republicans’ power would break down — and where tea party groups that want to see all-out war with Obama could find themselves disappointed. It’s also where some top Republican strategists are warning the party not to get too focused on blocking Obama’s policies rather than proposing their own.

“If it’s going to be about defining Republicans, then we get the initiative. If it’s going to be about responding to President Obama, then we potentially hand him the initiative,” said GOP pollster David Winston, who advises the House Republican leadership.

The wish list

If you talk to Senate Republicans, the wish list you get, after the standard “we’re not measuring the drapes” qualifiers, is a pretty lengthy one. They talk about entitlement reform — never with any specifics — and even tax reform, two ambitious goals they claim they’d like to take on once they have the power to write a budget. They’d take another vote on repealing the Affordable Care Act — something the GOP base still wants, even though enrollment is well underway — and then present alternatives to the law. And they’d push back hard on the EPA greenhouse gas regulations.

That’s all consistent with the signals being sent by McConnell. He has talked about how he’d run the Senate more openly and let the committee chairs determine the agenda. But he also promises he would challenge Obama at every turn, especially on the EPA regulations, using the spending bills as leverage.

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He also has told conservative activists that his own priorities would be to rein in Obamacare, pass a budget and hold hearings on the greenhouse gas regulations — a huge issue in his home state of Kentucky. Leadership aides also say the Senate agenda would be likely to start with jobs bills that have gotten bipartisan support in the House.

Other Republican leaders talk about even more ambitious plans, always in generalities. “We could pass a budget. That would be a start. That gives us more tools to do a lot of things,” said Senate Minority Whip John Cornyn of Texas. “We could pass tax reform. We could get spending under control.”

Senate Republican Conference Vice Chairman Roy Blunt of Missouri listed tax reform, entitlement reform and “holding regulators more accountable” as the big goals of a GOP Senate — but he declared that “the most important thing we could accomplish is to begin to create a sense of certainty about the government again” by encouraging job creation. “The president gets to decide whether he wants to be part of that or not,” Blunt said.

Rob Portman of Ohio, who outlined a Senate Republican jobs plan earlier this year, said a GOP majority would “change the dynamic in this town by giving the president an incentive to deal with us” on tax reform, regulatory relief and trade.

And GOP senators would like to set an overall goal of reducing regulations, with the hated EPA as a special target. James Inhofe of Oklahoma, who likely would become chairman of the Environment and Public Works Committee, says he would file Congressional Review Act challenges to every final EPA regulation that’s issued — the tool that allows Congress to block regulations, unless Obama vetoes the measures.

But can they get 60 votes?

The catch is that Republicans would not be able to land every veto-bait bill on Obama’s desk — certainly not all the ones conservative groups would like them to send him.

The most confrontational groups on the right want Republicans to use the Senate as a platform to draw clear contrasts with Obama by loading his desk with all the bills that get stuck in the Democratic Senate now, like a...