WASHINGTON — US Senate Majority Leader Mitch McConnell said Tuesday the upper chamber's budget will hew to the $1.07 trillion top-line of last year's budget deal, hemming in House fiscal conservatives who wanted a big budget cut.

"We will be using the top line that was agreed to last year in order to move forward on the Senate appropriations bills," McConnell, R-Ky., said at a Capitol Hill news conference on Tuesday.

The remarks came a day after Senate Democrats urged their GOP counterparts to begin writing spending bills based on the agreement amid delays on a Senate budget resolution. Top Democrats, led by Senate Minority Leader Harry Reid, D-Nev., sent McConnell a letter Monday affirming the Bipartisan Budget Act of 2015 (BBA) provides the necessary authority to set a top-line.

Senate Budget Committee Chairman Mike Enzi, R-Wyo., had announced Monday that his committee is postponing action on a 2017 budget resolution. Enzi said the committee has the authority to mark up individual bills due to language in the BBA Bipartisan Budget Act of 2015.

Enzi essentially stepped out of the way, according to a GOP aide, to "grease the skids" for appropriations measures.

Politically, the budget resolutions and spending bills have become a test for the GOP's ability to show it can govern and that new House Speaker Paul Ryan, R-Wis., can lead.

Within his caucus, Ryan is under competing pressures from defense hawks, who want to boost defense spending by roughly $20 billion, and fiscal conservatives, who want to trim entitlement programs and cut $30 billion.

House Budget Committee Chairman Tom Price, R-Ga., last week outlined a budget proposal to his caucus that would stick to the deal's trillion-dollar top line and come up with $30 billion in savings through stand-alone legislation.

Despite reports the House Budget Committee would vote on a budget resolution as early as March 15, an aide said Tuesday there was nothing to announce with the resolution, "still in a holding pattern."

McConnell on Tuesday signaled he was sticking to the BBA numbers. Asked what he would do if the House passed a resolution with a lower number, he deferred to Enzi.

"I know they're trying to figure out exactly how to deal with that," McConnell said. "But regardless, we have the top line for this year and we're going to go forward with appropriations."

McConnell was confident Democrats would not attempt to obstruct the process, which they might do to oppose eventual policy riders on the measure or in retaliation for the GOP's block on Supreme Court nominees.

"I don't believe they will," McConnell said. "I think we're going to have a pretty successful appropriations process."

Prior to McConnell’s optimism Tuesday, delays on the budget resolution stoked analysts’ predictions there would no budget before the end of the fiscal year. Instead, several analysts on a Center for Strategic and International Studies panel in Washington, D.C., on Monday said the gridlock could yield a continuing resolution to fund the federal government. 

"I think it's safe to say we'll start the year on a continuing resolution because there is a long track record of doing that," said CSIS budget expert Todd Harrison.

A CR is a stop-gap spending measure that allocates federal funding at the previous year's level. For the Pentagon, a CR that lasts six months or longer can derail the Pentagon's intricate multi-year planning process, particularly because CR's freeze new-start acquisition programs and transitions into production.

"When you get these potentially year-long disruptions that come seemingly at random, it really undermines the effectiveness of the system," said Andrew Hunter, director of the Defense-Industrial Initiatives Group at CSIS.

Relief from this repetitious cycle for the Defense Department will come after the election cycle, with the new president and potentially new dynamics in the House and Senate, which are both in play, said former House Armed Services Committee staffer Roger Zakheim, now a presidential campaign advisoer to Sen. Marco Rubio, R-Fla.

"If you're just looking at it through the lens of the Department of Defense," Zakheim said, "what they need is a new political reality."

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