Updated at 8:42 a.m. | While celebrating Senate passage of a fiscal 2018 budget resolution, President Donald Trump on Friday predicted the GOP holdout on that bill will vote for a follow-on tax measure.

The Senate on Thursday night adopted a budget measure altered as the final vote approached to allow House Republicans to adopt it and avoid a conference committee. The move is an attempt to get a final package of tax cuts and code changes to Trump’s desk faster.

The budget was adopted along party lines, 51-49, with only one GOP senator, Rand Paul of Kentucky, voting against it. But Trump used a Friday tweet to predict that Paul’s vote will be in the yes column when the tax bill hits the Senate floor.

Trump noted in the tweet that Paul voted against the GOP-crafted budget measure, but he then wrote this: “he will vote for Tax Cuts.”

The Budget passed late last night, 51 to 49. We got ZERO Democrat votes with only Rand Paul (he will vote for Tax Cuts) voting against…..

— Donald J. Trump (@realDonaldTrump) October 20, 2017

Sen. Lindsey Graham of South Carolina and other Republicans are warning their colleagues that a failure on taxes, after the fits and starts on health care, could spell doom for their party in the 2018 midterm elections.

The budget measure contains a special rule called reconcilation that, should the House adopt it, allow Senate GOP leaders to pass the coming tax measure with 51 Republican votes — Vice President Mike Pence would be standing by to cast the decisive 51st, if needed.

Paul’s support would make the path to 50 GOP senators easier, and Trump has been courting him.

The president and Paul appear to have a good working relationship. The duo golfed together on Oct. 15 at Trump’s resort in the Washington, D.C., area.

Sergio Gor, a Paul spokesman, told White House pool reporters that day that his boss “considers President Trump a personal friend.”

“They had a great time playing today,” Gor said, “and discussed multiple initiatives that they can work on together going forward.”

Gor had not responded to a request for comment on the president’s prediction about the tax bill. But his boss responded to Trump a few hours later via his own tweet, urging his House and Senate colleagues to act fast.

I’m all in for tax cuts @realDonaldTrump. The biggest, boldest cuts possible – and soon!

— Senator Rand Paul (@RandPaul) October 20, 2017

In a Thursday night statement, Paul explained his vote against the Republican-crafted budget plan this way: “Today, the Senate considered a budget that simply didn’t measure up and spent too much.”

“I could not in good conscience vote for a budget that ignores spending caps … and simply pretend it didn’t matter,” he said. “We can be for lower taxes AND spending restraint.”