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With President Obama hitting the throttle on health care reform, Tea Party opponents are reaching for the emergency brake.

But will they be too late?

The president, who just two months ago said that jobs creation would be Washington's No. 1 focus, has set an aggressive schedule for completing work on the bulk of the year-in-the-making health care package -- and he may be getting the jump on the raft of Tea Party events set for the coming weeks.

The Tea Party Express, a state-by-state caravan of conservative activists, won't kick off until March 27. The next major set of rallies is on Tax Day, April 15. A number of Tea Party groups are planning anti-health care bill town hall meetings, but the bulk of them aren't expected until later in the month.

Meanwhile, the White House has set a March 18 deadline for the House to pass the Senate version of the health care bill and the president is hitting the road to keep the cameras on him during that period. He pressed that deadline at Monday's rally outside Philadelphia, where he urged the crowd to help "get us over the finish line these next two weeks." And health care reform supporters staged a demonstration Tuesday in Washington, making noise outside a conference for the insurance industry.

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Tea Party groups have started descending on Washington to visit, and apply pressure to, fence-sitting House Democrats, with plans to stage a Capitol Hill rally two days before Obama's deadline. Midwestern Tea Party activists and Republican officials will also band together to try to build some counter-momentum when Obama visits St. Louis Wednesday for another rally -- but Republicans acknowledge the possibility of being steamrolled.

"It's very troubling. This hinges on so many things," said St. Louis Tea Party co-founder Dana Loesch. "We're just going to watch and kind of hold our breath."

Obama is putting his back into the latest, and perhaps final, push for a health care package, dusting off his "fired-up" campaign persona as he takes the pitch on the road. Congressional Democrats are pushing back on the deadline for passage, but the White House insists it's now or never on health care reform. White House Press Secretary Robert Gibbs said Tuesday that Obama might visit more cities before he leaves for Indonesia later this month.

"The need is great. The opportunity is here. Let's seize reform. It's within our grasp!" the president shouted at the end of his speech Monday in Philadelphia, where Tea Party activists protested nearby.

The White House Web site is also part of the president's campaign, with the official presidential blog sending out "Health Reform by the Numbers" postings -- Tuesday's number factoid was $1,115, or the average monthly premium for employer-sponsored family coverage.

But there's hope for opponents of the measure in the prospect that no matter the mood of the public, Democratic leaders just might not have the votes in the House.

"They have a lot of serious lifting to do between now and two weeks," said Steve Taylor, spokesman for Rep. Todd Akin, R-Mo., who is hosting a town hall meeting outside St. Louis Wednesday morning via video feed with other local Republican officials to blast the Democratic plan. That meeting will be followed by a Tea Party protest downtown across the street from an Obama fundraiser later in the day.

Though Michigan Democratic Rep. Bart Stupak, who has threatened to torpedo the bill with some allies over concerns about federal funding of abortion coverage, told The Associated Press Monday he was "more optimistic" than before about a deal, his office urged caution in a statement Tuesday. The statement said Stupak "remains optimistic," but that he "has not reached an agreement" yet on abortion funding.

And with so many deadlines blown in the course of the health care debate so far, lawmakers aren't reacting warmly to Obama's setting of a new one.

Senate Finance Committee Chairman Max Baucus, D-Mont., on Tuesday called the March 18 deadline a "steep climb" for the House.

"I don't want to give dates," he said. "All I know is deadlines are generally more of a problem than an opportunity."

The tentative plan is for the House to pass the Senate version and then for the Senate to move a package of changes to bring it more to House Democrats' liking, possibly using the "reconciliation" process which would allow it to pass with a simple, 51-vote majority. But this, as Baucus noted, has created deep distrust among House Democrats who fear their Senate colleagues will betray them and never follow up with a second bill.

"There's considerable mistrust," Baucus said.

"None of us have mentioned the 18th except Gibbs," House Majority Leader Steny Hoyer said.

Gibbs said Tuesday he thinks the March 18 deadline is still realistic.

Fox News' Trish Turner and Chad Pergram contributed to this report.