Looking for a measure of the political behavior of Marylanders when they choose their U.S. senators, Metro Scene took a tour through the all-time compilation of congressional biographies -- a book as thick as an unabridged dictionary -- and discovered some illuminating facts.

Since the popular election of senators began in 1913, Maryland has been represented by 15 men, seven of them from Baltimore City (although two had strong Eastern Shore backgrounds).

But just one, Sen. Blair Lee (D), who served from 1914 to 1917, came from Montgomery County (and, interestingly, he was the first person in the entire nation ever popularly elected to the Senate. Members previously had been elected by state legislatures. Lee was chosen in a special election to replace a senator who had died). And just one senator, Daniel B. Brewster (D), 1963-69, came from Baltimore County.

If past behavior is any guide -- we don't claim it necessarily is -- the odds seem long for the two suburban Democrats, Rep. Michael D. Barnes of Montgomery and Baltimore County Executive Donald Hutchinson, who seek to succeed retiring Sen. Charles McC. Mathias Jr.(R).

On the other hand, Marylanders rarely have chosen two Baltimoreans to serve simultaneously in the Senate. The most recent instance was Herbert R. O'Conor (D) and John Marshall Butler (R), who were there together from 1963 to 1965. Because the holdover senator, Paul S. Sarbanes (D), is from Baltimore, the tradition of geographic balance could pose a problem for Rep. Barbara Mikulski and, if he runs, Gov. Harry Hughes, both legal residents of the city. Hughes, however, has an Eastern Shore background.

Since the first Congress in 1789, Maryland has sent 54 men (but no women) to the Senate. In those 197 years, 18 came from the Eastern Shore, 16 from Baltimore, five from the Western Maryland counties beyond the Blue Ridge, and a sprinkling from other counties (including two each from Frederick and Howard and one each from Prince George's, Charles and Anne Arundel).

The high Eastern Shore figure resulted from a rule, a written one for many years and honored by tradition into this century, that reserved one seat for east of the Chesapeake Bay and one for west of the bay. Since popular elections began in 1913, no legal resident of an Eastern Shore county has been chosen.

Of the 15 in that group, seven came from Baltimore, two from Harford County (Millard and Joseph Tydings, father and son), two from Allegany (J. Glenn Beall and J. Glenn Beall Jr.), one (Mathias) from Frederick, one from Cecil and, as mentioned previously, one each from Montgomery and Baltimore counties.