ABC’s Amy Walter reports: The latest ABC News analysis shows that while Republican candidates have gained ground in senate races in three key swing states – Pennsylvania, Florida and Wisconsin, Democrats chances have improved in California, Delaware and Washington. The most recent polling in Florida shows Republican Marco Rubio building a strong lead thanks in part to the fact that support for Gov. Charlie Crist (I) has started to collapse and Democrat Kendrick Meek still has been unable to get much traction. In Pennsylvania, ex-Rep. Pat Toomey (R) is butting up against the 50% mark against Democrat Joe Sestak. Sestak hasn’t led in this race since May. In Wisconsin, Dem. Sen. Russ Feingold seems to be in free-fall – a recent CNN poll showed him trailing businessman Ron Johnson by 6 pts. 45% to 51%. Meanwhile, new polling in California shows Sen. Barbara Boxer (D) extending her lead over ex-HP CEO Carly Fiorina, while Sen. Patty Murray (D) of Washington has been at or over 50% in the latest polls. At this point, we see five Dem-held states leaning toward the Republican: Pennsylvania, Indiana, Arkansas, North Dakota, and Wisconsin. There are no Republican-held seats that lean toward the Democrats. That means in order for Republicans to take control of the Senate, they need to hold their two most vulnerable seats (Missouri and Kentucky) while also picking up at least five of these eight vulnerable Democratic-held seats : Colorado, Illinois, Nevada, Washington, California, West Virginia, Connecticut and Delaware. At this point, recent polling suggests that Republicans' strongest opportunities are in Colorado, Illinois, West Virginia, and Nevada. There’s not been any recent polling in Missouri and conflicting polls in Kentucky. Still, it’s hard to see Democrats win either state. In the House, we see 199 seats where Democrats are favored compared to 191 seats where Republicans are favored. That leaves 45 seats, 42 of which are held by Democrats, as the battleground for House control. In order for Democrats to retain control, they’d need to win 19 (or 42%) of those 45 toss up seats. Republicans would need to win slightly more – 27 (or 60%) to take control. However, it’s important to point out that all the movement in the last couple of weeks has been toward Republicans. Seven Democratic-held seats we listed as Toss-Ups last week we’ve since moved to Lean Republican.