Berlin - Two months before a German general election, Chancellor Angela Merkel continued to ride high Wednesday with her main opponent suffering a fresh drop in an opinion poll.

Frank-Walter Steinmeier, a Social Democrat, slumped from 20 to 17 per cent on a survey question, who would you elect chancellor if you could? In fact, voters can only elect the legislature, which then picks the chancellor.

In the weekly poll by the Forsa company, incumbent Merkel's rating on the same question rose from 58 to 60 per cent.

Vice-Chancellor Steinmeier's result was his worst since he was nominated 11 months ago as Social Democratic (SPD) standard-bearer.

His Social Democratic Party (SPD) was caught off foot this week when one its ministers, Ulla Schmidt, who has the health portfolio, confirmed that she had used an official car while on holiday in Spain.

As a result, Schmidt has been left off Steinmeier's "shadow cabinet," details of which emerged during a convention of SPD leaders.

Steinmeier's proposed ministerial team, should the SPD remain in government, is to include several high profile women, German Press Agency dpa learned a day ahead of the official nomination.

SPD Vice-Chair Andrea Nahles is to be nominated for the education brief, Mecklenburg-Pomeranian minister Manuela Schwesig will be responsible for politics and the head of the defence commission Ulrike Merton will take on the party's defence portfolio.

Barring Schmidt, Steinmeier's team is to include all current SPD ministers.

Speaking to journalists on the fringes of the party talks, Steinmeier said his team stood for "dynamism and departure," adding that the SPD had "not only the better heads, but also the better ideas," to move Germany forward.

Foreign Minister Steinmeier is set to announce his competence team in full on Thursday. Germany votes on September 27.

The polls showed support for Merkel's Christian Democratic Union and its Bavarian ally at 38 per cent, up 2 points, while its likely coalition partner, the Free Democrat Party, would win 13 per cent, down 1 point.

The Forsa poll, commissioned by Stern magazine and RTL television, gave the SPD a steady 23 per cent.

However, it was carried out before Schmidt's holiday transport arrangements became news and opponents accused her of wasting taxpayers' money.

Another company's poll last week rated them at 37, 13 and 25 per cent respectively.(dpa)