WASHINGTON — Democrats are just shy of gaining enough support in key battleground states to capture control of the Senate. Voters’ sense that the country is on the wrong track may offer opportunities to close that small gap in the final days of the congressional election.

A new Bloomberg/Los Angeles Times poll of five states with the most hotly contested Senate races shows Democrats with the lead in Ohio, New Jersey, and Virginia. Republicans are ahead in Tennessee and Missouri. In all five contests, the margins were close enough that the advantage could change by Election Day.

Most specialists say the Democrats must win at least four of these five races to obtain the net gain of six seats they need to take control of the Senate. If the poll results hold, Democrats would be within one seat of the 51-vote majority in the chamber. “It’s going to be a tough road for them,” the Times polling director, Susan Pinkus, said. “But it could be the year of the Democrat,”she said. “It all hinges on the getting out the vote, energizing your base.”

There’s good news in the poll for the Democrats’ bid to win the 15 seats they need to take over the House, as voters in all five states said they would prefer Democrats to control Congress after the November 7 elections. Most significant may be the 24-point Democratic advantage in Ohio, where as many as five Republican seats could be in jeopardy.

The Democrats are also preferred by a wide margin in New Jersey and Virginia, states with vulnerable Republican-held House seats. In Missouri and Tennessee, the focus is on the Senate contests, with no close House races anticipated by specialists. On the Senate outlook less than two weeks before the elections, both sides agree Democrats hold leads in three Republican-held seats, Pennsylvania, Rhode Island and Montana, and in 16 Democratic-held seats. If those advantages hold, Democrats have to score a net gain of three more seats to obtain a majority.

Election experts Charlie Cook and Stuart Rothenberg both say there are four toss-up states — Missouri, Virginia, Tennessee, and New Jersey, where Democrats are defending a seat — and both agree Ohio is tilting toward the Democrats.

The public is more negative about the direction of the country than in 1994, when Republicans swept Democrats from control of both chambers. The poll showed that three-fifths of respondents or more in each state say the country is on the wrong track, compared with about half of voters in 1994.

The poll found that in all five states except Tennessee, those who said their vote would be affected by President Bush’s policies also said by almost a 2-to-1 margin that those policies would have a negative effect. The poll data were collected separately in each state by telephone October 20–23.

In the Ohio Senate race, Rep. Sherrod Brown, a Democrat, is ahead of Senator DeWine, the Republican incumbent, by 47% to 39%.The sample of 507 likely voters has a margin of error of 4%.

Ohio helped tip the presidential election in Mr. Bush’s favor in 2004. Since then, the state’s Republican Party has been rocked by a series of ethics controversies, including, most recently, Rep. Bob Ney’s guilty plea in the Jack Abramoff lobbying scandal.

The economy is also a major issue in Ohio, which had a 5.7% unemployment rate in August, the nation’s eighth-highest. By a margin of 56% to 30%,Ohio voters said they prefer Democrats to handle the economy, the poll found.

Mr. Brown, 53, holds a 21-point advantage among women and a 12-point lead among independents. Fifty-six percent of suburban and city voters favor Mr. Brown, while Mr. DeWine, 59, gets 63% of the rural vote. Jim Friedman, a lawyer who has run campaigns in the Midwest for presidential candidates such as Jimmy Carter, said he told Democrats that “if things start to go bad, Mike DeWine will be in a freefall,” and “that’s exactly what’s happened. The war’s gone bad. The Ohio economy is on the rocks.”

Democrat James Webb, a Vietnam veteran who served as President Reagan’s Navy secretary, has a narrow 47-to-44% lead over Senator Allen, the Republican incumbent, in the Virginia Senate race. The sample of 385 likely voters has a margin of error of 5%. Mr. Webb, 60, is a critic of the Iraq war; Mr. Allen, 54, is a former governor and representative who backs Mr. Bush.