As newly empowered Democrats forge ahead with their own agenda, some items may make it to his desk as prime candidates for veto.
One might be a recycled version of the stem-cell funding bill that drew Mr. Bush's lone veto last July. Other possibilities include measures that would raise the minimum wage without offsetting tax breaks for businesses, fully put in place the Sept. 11 commission's recommendations and curb oil-industry subsidies.
The Democratic takeover of Congress and the planned 100-hour burst of legislation sent parliamentary experts in both the administration and Congress scurrying to dust off the manual on vetoes and to brace for a possible onslaught.
In the new Congress, just days old, promises of bipartisanship still fill the air. Such pledges, however, may be put to the test in no time.
With Iraq overshadowing everything, any attempts by lawmakers to cut funds or intrude on Mr. Bush's war-making decisions could invite veto talk. Mr. Bush is set to announce a new Iraq strategy this week in a speech expected to call for more troops and aid.
Democratic leaders have not expressly threatened to use Congress' purse-string powers to alter the course of the war. But House Speaker Nancy Pelosi, and Senate Majority Leader Harry Reid, both Democrats, were quick to signal that the days of a free hand are over for the Republican president.
In the November elections, voters "rejected an open-ended obligation to a war without end," Pelosi said. For Reid, "no issue in this country is more important than finding an end to this intractable war."
The odds on vetoes always have favored presidents, no matter which party controls Congress. There have been 2,551 presidential vetoes since George Washington became president in 1789. Only 106 have been overridden.
Mr. Bush will seek common ground with Democrats on issues such as the minimum wage, education legislation and immigration overhaul, but "he won't hesitate to veto things he doesn't like," Republican strategist Charlie Black said.
"I don't think there will be very many things he has to veto. But if he does, he'll certainly be able to sustain them," said Black, who is close to the White House.
Even more bills might draw vetoes if not for a procedural rule in the 100-member Senate that makes it hard for contentious legislation to pass without 60 votes — instead of a simple majority of 51. Thus, Republicans should be able to keep many veto-threatened bills from even making it to the president.
White House officials are not telegraphing specific possible vetoes in advance, though they are studying possible candidates.
Would Mr. Bush veto spending bills that contain pet projects — known as earmarks — after warning Congress to end the practice and urging a balanced budget by 2012?
"Well, let's just see what happens when we get appropriations bills," White House spokesman Tony Snow said. "There seems to be a movement toward fewer earmarks. Maybe that issue never comes up."
In the Senate, the Democratic advantage is just 51-49, made up of 49 Democrats and two independents who usually vote along with the Democrats. In the House, the Democrat-Republican breakdown is 233-202.
Once a president vetoes a bill, lawmakers have 10 days (excluding Sundays) in which to override it. Overturning a veto takes a two-third majority of those present and voting in both chambers. If all 100 senators vote, a veto-override requires 67. If all 435 House members are voting, 290 votes are needed.
Mr. Bush's only veto was a rejection of legislation in July to increase federal money for embryonic stem-cell research. The bill had much bipartisan support, but not enough.
The House voted 235-193 to override his veto — 51 short of the 286 that would have been needed (two-thirds of the total votes of 428). Because only one chamber is needed to sustain a veto, the Senate did not have to act. Mr. Bush's action stood.
Mr. Bush's one veto is a little misleading. Actually, he has made more than 140 veto threats since taking office.
In many cases, Republican leaders just modified the legislation to make it more to Mr. Bush's liking. In other instances, he added "signing statements" flagging parts he disputed on constitutional grounds.
Why has not he issued more vetoes? Because he usually got what he wanted from the Republican Congress, Mr. Bush suggested at a news conference last summer.
Now, all has changed.
"It's far more likely that he's going to veto spending bills than in the last Congress. He won't be taking on his own party," said Norman Ornstein, a scholar at the American Enterprise Institute who closely follows Congress.
Mr. Bush's predecessors used the veto far more than he has so far.
Mr. Bush's father, George H.W. Bush, vetoed 44 bills in his single term and had only one overridden. President Bill Clinton vetoed 37 bills in eight years and two were overridden. President Ronald Reagan vetoed 78 bills over eight years and nine were overridden.
President Gerald Ford, laid to rest last week after a state funeral at which he was praised for practicing the art of political compromise, vetoed 66 bills in 2 1/2 years and had 12 overridden.
That ties with President Harry Truman (1945-53), who also had 12 overrides — of 250 vetoes. The only president with more overrides was Andrew Johnson (1865-69), with 15 of his 29 vetoes overturned.