WASHINGTON -- Republican George W. Bush's lead over Democrat Al Gore fell to three points in Wednesday's Reuters/MSNBC national daily tracking poll, and Gore increased his strength in the key states of Pennsylvania and Michigan.

The national survey of 1,211 likely voters in next Tuesday's election, conducted Sunday through Wednesday by pollster John Zogby, found the Texas governor with 45 percent and the vice president with 42 percent. That represented a net pickup of two points for Gore in the past 24 hours.

Green Party nominee Ralph Nader polled 5 percent; Reform Party candidate Pat Buchanan stayed at 1 percent; Libertarian Harry Browne had 1 percent, and the rest remained undecided.

The race remained within the statistical margin of error of plus or minus three percentage points. A candidate would have to be more than six points in the lead to be outside that zone of uncertainty -- something neither man has achieved since the poll began Sept. 29.

Separate polls of around 600 likely voters in each of nine key battleground states showed a more volatile picture, with Gore increasing his lead in Michigan and Pennsylvania while Bush narrowed the gap in Illinois, Florida and Wisconsin. These state polls had statistical margins of error of plus or minus four points.

REMAINS UNPREDICTABLE

"Basically, this election remains unpredictable and the key battlegrounds are still in play. But Gore has some momentum is Michigan and Pennsylvania, which could loom very large on Election Day," he said.

The results showed Gore still seven points ahead in the key state of Florida. But Bush made a big move in Wisconsin, cutting Gore's lead to three points.

In total, 153 votes in the Electoral College are up for grabs in those nine states. At the moment according to these polls, Gore would win 110 and Bush would take 43 of those votes.

These are the complete state-by-state results for Wednesday, including the net change since Tuesday:

A total of 270 electoral votes are needed to be elected president. Most analysts believe both candidates have definitely secured about 200, leaving some 138 to be fought over that will decide the election.

SLIGHT DEMOCRATIC LEAD FOR HOUSE

In the equally tight race for the House of Representatives, voters preferred the Democrats by two percentage points in the national poll. The Democrats need a net gain of seven seats to regain control from the Republicans.

Several tight Senate races were also within the margin of error. In New York, Republican Rick Lazio led Democratic first lady Hillary Rodham Clinton 47 percent to 45 percent.

In Missouri, the late Gov. Mel Carnahan, whose wife says she would serve in his place if he won, led Republican Sen. John Ashcroft 47 percent to 45 percent. Carnahan was killed in a plane crash Oct. 16 but his name remains on the ballot.

In Florida, Democrat Bill Nelson's lead over Republican Bill McCollum has narrowed to 42 percent to 37 percent.

In Washington state, Republican Sen. Slade Gorton has a one point lead over Democrat Maria Cantwell, 47 percent to 46 percent.

The biggest move was made by Democrat Debbie Stabenow in Michigan, who now leads Republican Sen. Spencer Abraham 48 percent to 39 percent, outside the margin of error.

Democrats need to pick up five seats to regain the majority in the Senate.

In the national presidential poll, men backed Bush, 49 percent to 37 percent; women preferred Gore by 47 percent to 41 percent as the electorate continued to show a substantial gender gap.

Bush led among whites by 59 percent to 38 percent while Gore was ahead among Hispanics and blacks.

Reuters and MSNBC will release a new poll every day at 6:30 p.m. until the election.