Reading through election coverage in some major US newspapers (online, of course) Leighley's theory about the breakdown of that coverage seems to be confirmed. The largest segment of coverage is stories about the horserace and strategy, such as the following from the Washington Post's election coverage :
Both Parties Sensing Tighter House Races describes the respective chances of each party, and the effects of events like falling gas prices and efforts to focus the campaign on terrorism. There is no discussion of differences between the parties, just a prognostication of their prospects.
And this: In a Pivotal Year, GOP Plans to Get Personal: Millions to Go to Digging Up Dirt on Democrats which describes unadulterated strategy, without any disturbing details about things that matter:
"Republicans are planning to spend the vast majority of their sizable financial war chest over the final 60 days of the campaign attacking Democratic House and Senate candidates over personal issues and local controversies, GOP officials said.
The National Republican Congressional Committee, which this year dispatched a half-dozen operatives to comb through tax, court and other records looking for damaging information on Democratic candidates, plans to spend more than 90 percent of its $50 million-plus advertising budget on what officials described as negative ads."
And what about the Democrats?
"As Republicans try to localize races, Democrats' hopes for the most part hinge on being able to nationalize the election and turn it into a referendum on the Iraq war, President Bush, and the performance of the Republican Congress -- all faring poorly in polls this year."

Meanwhile, in the latest case of campaign issues taking control of media coverage of a race, defined by Leighley as issues which do not have any inherent policy relevance and are only issues in the context of a campaign:
The New York Times reports on the latest blunders of George Allen's senate race. The headline should have read "Senator Manages to Destroy his Re-election Prospects by Insulting Every Ethnic Group Imaginable". The Washington Times takes a strategic perspective on this as well:"Allen urged to focus on successful record", I guess instead of trying to think of more creative slurs.
Other stories tended to focus on how candidates' race would influence a congressional campaign, or how Democrats have realized the importance of emphasizing faith. Not exactly in depth on the issues. On the other hand coverage seemed to be objective.
In contrast, the blogosphere seems even less substantive. Daily Kos , for example, has a stronger focus on the numbers than the mainstream media. Perhaps because their audience is largely people who have made up their mind, instead of providing analysis and discussion of issues, posts just give the latest poll numbers and predict Democratic takeover. Other posts merely celebrate Republican gaffes. Overall, probably not the best way to get informed of policy debate. Same goes for other blogs such as Atrios: insults yes, deep analysis less.
Personally, I recommend The New Republic.