Rob Zerban, (pictured) the Democrat challenging Paul Ryan, has a shot at beating Ryan in November, the first poll done for Zerban's campaign shows.

One of the hurdles for a challenger in a Republican district is to demonstrate that there's a real chance for victory. There is a lot of competition for campaign financing, to put it mildly, and decisions made in Washington, DC about which races to target can turn the contribution spigot on or off.

Zerban's pollster, Paul Maslin, says in a memo that Zerban "is well-positioned to give incumbent Paul Ryan the toughest fight of his career, with a very good chance to upset him."

More at The Paul Ryan Watch.