Computerworld - Twitter launched an interactive map to shine a spotlight on which of the presidential candidates' tweets gain the most traction in different areas of the country.

As election day nears, President Barack Obama and his Republican challenger, Mitt Romney, are tweeting about a wide variety of issues - job creation, women's health and foreign policy. A big question, though, is what tweets, and what topics, are catching people's attention.

Twitter is offering voters, and the campaigns, a look at what issues are the most important to voters with a new interactive map.

"Prominent issues in this year's campaign range from Pell Grants for students to Medicare for the elderly, from coal production to clean energy," wrote Miguel Rios, a member of Twitter's analytics team. "Of course, the salience of these issues varies greatly by state.... We've built a visualization that illustrates people's reaction to and engagement by state to Tweets from @MittRomneyand @BarackObama.

Twitter is running what it has dubbed a Political Index that measures how hot or cold user's sentiments are running on the two candidates based on the tweets being posted about them.

The new interactive map, which went live late this week, is focused on how people - state by state - engage with the candidates' tweets.

Rios explained that individual tweets are represented on the map by a bar. The more engagement, such as retweets and comments, for a particular tweet, the longer the bar is. Clicking on the bar shows the user state-by-state engagement level.

Users also can search for specific terms to see tweets from @BarackObama and @MittRomney about specific campaign topics, added Rios. For instance, type in the word "Medicare" and the map will show which states have engaged the most with tweets about this topic.

Click on a particular state and you get the most relevant tweet topics for that state. For swing state Florida, for example, the most relevant topics are terrorism, foreign affairs and retirement. For Ohio, it's gay rights, taxes and education.

The micro-blogging site has been a critical tool in watching citizens' reactions to the candidates and the topics they bring up.

During the presidential debates, it was easy to spot which topics touched off a firestorm of tweets. For example, during the second presidential debate last month, Twitter's site actually staggered for several minutes at a time after the candidates dealt with issues including China, immigration and women's health care.