Trump pledges biggest tax cut after Senate approves $4 trillion budget

President Donald Trump promised tax cuts today "which will be the biggest in the history of our country!" following Senate passage of $4 trillion budget that lays the groundwork for Republicans' promised tax legislation.

Republicans hope to push the first tax overhaul in three decades through Congress by year's end, an ambitious goal that would fulfill multiple campaign promises but could run aground over any number of disputes. Failure could cost the GOP dearly in next year's midterm elections.

The budget plan passed on a near party-line vote late yesterday includes rules that will allow Republicans to pass tax legislation through the Senate without Democratic votes and without fear of a Democratic filibuster.

Nonetheless, the GOP's narrow 52-48 majority in the Senate will be difficult for leadership to navigate, as illustrated by the Republicans' multiple failures to pass legislation repealing and replacing "Obamacare."

The final vote on the budget was 51-49 with deficit hawk Sen. Rand Paul of Kentucky the lone opposing GOP vote.

Trump insisted over Twitter Friday that Paul would be with him in the end on taxes, even though the senator has been critical of the tax package as it's emerged thus far.

Trump wrote, "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........This now allows for the passage of large scale Tax Cuts (and Reform), which will be the biggest in the history of our country!"

The House has passed a different budget but House Republicans signaled they would simply accept the Senate plan to avoid any potential of delaying the tax measure.

"I look forward to swift passage and to working with the president on tax reform," House Budget Committee Chairman Diane Black, R-Tenn., said today.

Republicans are looking for accomplishments following an embarrassing drought of legislative achievements despite controlling both chambers of Congress and the White House.

Republican lawmakers publicly admit that failure on taxes would be politically devastating with control of the House and Senate at stake in next year's midterm elections.

"It would be a complete disaster," Sen. Lindsey Graham, R-S C, said after the final budget vote.

But Republicans are split on taxes. A restive rump of House Republicans from high-tax states like New York, New Jersey, Illinois and California staunchly oppose the tax plan's proposed elimination of the federal deduction for state and local taxes. They maintain it would hurt low- to mid- income taxpayers and subject them to being taxed twice.

Their vocal opposition has led Republican leaders in Congress like House Speaker Paul Ryan and Rep. Kevin Brady, R-Texas, who heads the tax-writing Ways and Means Committee, to hear out the fractious GOP members and seek a compromise with them.

At the same time, the White House is making overtures to conservative Democrats in the House and Democratic senators from states that Trump won in the 2016 election. Most heavily courted have been Sens. Claire McCaskill of Missouri, Joe Manchin of West Virginia and Heidi Heitkamp of North Dakota.

The trio dined this week at the home of daughter Ivanka Trump and her husband, Jared Kushner, both top advisers to Trump.